The present invention relates to a shaving system in which more than one shaving action is performed during a shaving operation, to methods of shaving, and to blade unit sub-assemblies and cassettes for use in such apparatus and methods.
A shaving system having one stationary razor blade and one linearly reciprocating razor blade is known from Swiss patent CH199 850 (Metzler et al.). This arrangement has two double-edged sided razor blades (38, 39) of the “Gillette type” (see page 3, left column, line 21) and reciprocates one razor blade (39) while the other razor blade (38) of the two is stationary. The moving razor blade is actuated by pins 31 on a linearly reciprocating pusher 30, the pins 31 engaging in the short slots 40 of the moving blade 39, whereas the stationary blade 38 has longer clearance slots 41 so that the pins 31 move without moving the stationary blade 38 (page 3, left column, lines 4 to 18). The razor blades are positioned so that either the top razor blade moves and the bottom blade is stationary, or the bottom razor blade moves and the top blade is stationary (page 3, right column, lines 3 to 9). Guard (24, 25) is positioned in front of the forward blade.
Systems are known in which a rotating guard member is positioned in front of a sharp safety razor, e.g. U.S. Pat. No. 5,022,154 (Johnson). A shaving system having a plurality of pairs of rotating sieve-like guard elements positioned in front of and feeding hairs to razor blades positioned behind the rotating guards is known from German patent DE 1 182 554 (Brand). The roller-guard and razor blade pairs are positioned around the semi-circular periphery of the shaver housing (FIG. 2). The cylindrical roller guard 1 is rotated by having its friction roller end 13 driven by a friction driver wheel 4. Each razor blade 2 is mounted on a bridge 3, and are either static or driven in linear reciprocation shown by arrow 24 in FIG. 6, see column 3, lines 49 to 52. When the razor blades are linearly oscillated as in FIG. 6, they are driven by contours 19 in cam wheel 20 against restoring springs 2a (FIG. 3), and the blade edge can have serrations 22. As described at column 4, lines 27 to 39, and FIG. 6, the roller guards have rectangular openings 26 formed by the framework of the roller guard, and in operation beard hair enters the openings 26 and by rotation of roller guard 1 is pushed against the razor blade 2 for cutting.
A shaving system having both a static guard and a rotating, profiled feeder positioned in front of a sharp razor blade is known from German patent application DE 25 03 175 (Hansom). This document shows two types of embodiments, the first that of FIGS. 1-5, and the second that of FIGS. 6-8. In each, the static guard 5 or 36 is positioned in front of a single wet safety-razor type blade edge 4 or 33, which defines with the sharp edge a skin plane 7 or 44, and a beard hair is shown as 13 or 45 (FIG. 1, 8). Between the static guard and the blade edge is a rotating feeder. The rotating feeder of FIG. 1 is a cylindrical sleeve 8 defining three longitudinal slits which define continuous edges 11. In operation described at page 5, rotation of the edges 11 effects that hairs 13 are brought into contact with sharp cutting edge 4 to be cut. Alternative versions of the rotating feeder are described at pages 5 to 6 that it is a rotating strip having two edges, and that the strip can be straight or spiral; or can be cross-shaped (FIG. 3); or toothed (FIG. 4); or a perforated sleeve 20 with openings 22 (FIG. 5), and the embodiments of FIGS. 1 to 5 do not disclose that the edges of the rotating feeder are sharp. In the alternative embodiment of FIG. 6 the rotating feeder is formed by a conventional drill bit shaft 23 having two spiral edges 25 which are sharp (page 7, lines 1-5), and shown in cross-section in FIG. 8. The DE 25 03 175 states that since the skin is flexible the drill bit shaft 23 is spaced from skin plane 44 so as to not contact the skin since otherwise the user will experience an undesirable burning irritation feeling.
Shaving systems comprising multiple foil-type units are known, e.g. from U.S. Pat. No. 6,098,289 (Wetzel et al.) which also discloses combinations of short hair cutters with a long hair cutter, or also U.S. Pat. No. 6,223,438 (Parsonage et al.) or U.S. Pat. No. 3,967,372 (Beck et al.).
Shaving systems comprising multiple razor-sharp blades are also known, e.g. from GB-A-1,460,732 which describes shaving cartridges comprising two parallel razor-sharp blades, and U.S. Pat. No. 5,661,907 (Apprille, Jr.) which discloses a shaving cartridge comprising three parallel razor-sharp blades.
It is also known to provide a long hair trimming unit comprising a pair of interacting blades at the upper side of the shaver alongside a foil-type reciprocating shaving unit, e.g. JP-A-2000-288267 (Hitachi Maxell).
It is further known to have non-cutting, hair-erecting scraper edges positioned adjacent or radially outward of the rotary cutter units on known rotary-type electric shavers such as sold by Philips Corporation. See WO 00/13859 (Barish), which discloses a rib-like, thin, blunt scraper member (232) surrounding each cutter (FIG. 20) and a common scraper member (242) (see FIG. 22) surrounding the several cutters. Allegedly, the scraper member tautens the skin and erects the hairs, but does not cut the hair, just before hairs are received within the slits of the electric razor cutter, for producing a closer shave when the electric shaver is used with a lubricating liquid for effecting a wet shave, as described at pages 13-15 therein. However, if such a construction is used without a lather when operated in a dry shaver mode, it will disadvantageously increase skin irritation. It is also known from United States published patent applications US 2001/0027608 A1 (Barish) and US 2001/0042308 A1 (Barish) that such scraper edges can be relatively sharp and formed as either a square edge (15a, see FIG. 5) or an outwardly extending edge (25d, see FIG. 6), but in both cases this edge does not cut hairs. Nonetheless, it causes such significant skin irritation that during normal use of the electric shaver, it is not meant to contact the skin surface being shaved; rather, these documents teach that the electric shaver must first be tilted obliquely (compare shaving position LA where the hair-erecting edge is not engaged, with the tilted position LA′ where the hair-erecting edge is engaged to erect hairs) to selectively engage the hair-erecting scraper where the user feels the electric cutter unit has missed a hair, which has the simultaneous disadvantage that the cutter unit is no longer at the intended orientation for efficient hair cutting. Indeed, other embodiments therein (FIGS. 7-8) teach that during a normal shaving action the scraper edges are completely out of contact with the skin. In other words, with these described devices, the user would be subject to skin irritation if he attempted to use the scraper edge constantly during normal operation of the electric hair cutter disc, and thus must forego the alleged benefit of a closer shave except in sporadic use where he determines that the electric hair cutter disc missed a spot, and he repeats the shave with the product tilted so as to engage the scraper edge into the skin and tolerate some irritation. This is also cumbersome and inefficient.
Another device is known from DE-A-34 28 631 A1 (Ebner) which discloses an electric shaver having a single foil-type reciprocating shaving unit together with an auxiliary blade element (4) disposed laterally of the main shaving unit in a recess of the shaving head and which, subsequent to completing the electric shaving operation, can be pivoted from a rest position (FIG. 5) into an outwardly extending operating position (FIG. 6) for removing stray long hairs which may have been missed during operation of the foil-type cutter unit. The documents explains at page 8, at the last paragraph of the disclosure, that the auxiliary cutting device (4) is deployed as an “emergency razor” when the battery has discharged There is however no suggestion that the foil-type cutter should be used in tandem with the blade unit and the geometry of the shaver would not make this feasible.
Combinations of hair manipulators and cutting members are also known, e.g. from WO-A-01/07212 and WO-A-01/07213 (Pragt).
Other types of shaving system are also known. For example, GB-A-1,444,960 (de Raemy) discloses a dry shaver having a cylindrically arcuate cutting surface defined by a plurality of cutting edges and means for rotationally reciprocating the cutter head about its longitudinal axis. In a preferred embodiment, the reciprocating cutter head is positioned beneath a cylindrically curved outer cutting foil. Further arrangements of this type are disclosed in GB-A-1,469,556 (Ascoli) and in GB-A-1,533,679 (Buchholz).
Another rotary appliance for removing hair is disclosed in WO-A-98/07551 (Garenfeld et al.), which comprises a rotary clamping device for clamping hair and subsequently extracting it at least partially from the skin, whereupon the hair is severed adjacent the skin by a separate shaver or hair trimmer arrangement (13, 29), consisting of a static shaver blade (33) adjacent the skin and a shearing blade (31) which reciprocate in shearing relationship. The appliance can be selectively set to a mode in which the oscillating shearing trimmer (13, 29) is decoupled from the drive, so that the appliance functions like a conventional epilator.
It has also been proposed in various published documents to provide in a shaving system a blade structure comprising a plate defining a plurality of apertures having annular sharpened shaving edges on the plate or formed in separate discs mounted to the plate. Systems of this type are disclosed in U.S. Pat. No. 5,604,983 (Simms et al.), U.S. Pat. No. 5,490,329 (Chylinski et al.), U.S. Pat. No. 3,702,026, U.S. Pat. No. 4,483,068, U.S. Pat. No. 4,807,360 and U.S. Pat. No. 5,153,992.
It has also been proposed to have a twin-blade assembly comprising two blade members secured for replacement, as a unit, in a plastics razor head of the wet shaving type, in order to have the ecological advantage of discarding the dulled blades and re-using the cartridge frame components, as disclosed in U.S. Pat. No. 5,551,153 (Simms).
As is well-known, the dry shaving system has advantages which are not shared by the wet shaving system, and vice versa. For example, the dry shaving system is exceptionally convenient for the user, does not require the application of liquid to the face and is comfortable. The wet shaving system, on the other hand, normally requires the application of a lubricant, such as soap, and for some users tends to produce more discomfort than the dry shaving system. It does however on the whole produce a closer shave, for most users, than a dry shaving system.
In spite of these known advantages and disadvantages, it has never previously been proposed to provide a hybrid shaving system combining the advantages of the dry shaving and the wet shaving systems without the attendant disadvantages.